Cigarette packer hopper automatic feeding device

ABSTRACT

An automatic cigarette packer hopper tray feeding device which comprises a tray for cigarettes, a feed conveyor and a container to receive the cigarettes from the tray, elevator means to transfer a tray of cigarettes from the conveyor to a means to overturn the tray of cigarettes and position the cigarettes in an orderly manner in the container and to return the empty tray to the elevator.

United States Patent Gianese [451 Apr. 11, 1972 [54] CIGARETTE PACKER HOPPER [56] References Cited AUTOMATIC FEEDING DEVICE UNITED STATES PATENTS [72] Inventor: Goifredo Gianese, Bologna, Italy 3,486,647 12/1969 Seragnoli ..2l4/307 1 Asslgneei AMF Incorporated 3,298,549 1/1967 Schmerrnund ..214/307 [22] Filed: Mar. 11, 1970 Primary Examiner-Gerald M. Forlenza [21] PP 18,598 Assistant Examiner-Lawrence J. Oresky Attorney-George W. Price and Eli Weiss [30] Foreign Application Priority Data June l7, I969 ltaly ..7107 A/69 [57] ABSTRACT An automatic cigarette packer hopper tray feeding device [52] U.S. Cl ..2l4/302, 214/307, 214/314 which comprises a tray for cigarettes, a feed conveyor and a [Sl] Int.Cl ..B65b 19/04 container to receive the cigarettes from the tray, elevator [58] Field of Search ..2l4/30l 302, 303, 307, 312, means to transfer a tray of cigarettes from the conveyor to a 21 /314 means to overturn the tray of cigarettes and position the cigarettes in an orderly manner in the container and to return the empty tray to the elevator.

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ATTORNEY PATENTEDAPR 1 1 I972 SHEET 7 BF 7 Q c w 1 w mm U a mm Q INVENTOR. GOFFREDO GlA/VESE ATTORNEY CIGARETTE PACKER HOPPER AUTOMATIC FEEDING DEVICE This invention relates generally to cigarette packers and, more particularly, to an automatic cigarette packer hopper feeding device.

In cigarette packers, feed hoppers are provided to store cigarettes to be packed in an orderly manner parallel to each other. This positioning of the cigarettes is required for the correct machine operation as the cigarettes are extracted in an orderly manner from the bottom of the hopper to form the various groups of cigarettes to be packed.

The hopper is generally fed with successive loadings by means of trays in which the cigarettes are methodically arranged in superimposed rows where the average number of cigarettes stored in each tray being from 3,000 to 4,000 cigarettes. The loading of the packer is effected by inverting the trays to permit the cigarettes therein to descend by gravity from the tray into the hopper and remain parallel to each other during their free fall.

However, as the present trend is to ever increasing output rates, the problem of feeding cigarettes to the packer hopper assumes increasingly greater importance. It should be noted that if the packer has a very high output rate, the cigarettes contained in the hopper will be processed very quickly. In practice, as soon as the cigarettes of the feeding tray have completely moved into the hopper, the tray must be replaced as quickly as possible with a full one. In fact, during the replacement of an empty tray with a full tray, the cigarette level in the hopper continues to descend and, if the replacement is not done quickly, the entering cigarettes, from the new tray, will have to fall a relatively long distance before reaching the cigarettes in the hopper. If the cigarettes are required to experience a free fall of any substantial distance, the maintenance of the parallelism of the cigarettes becomes difficult. In other words, the cigarettes could be positioned in the hopper in a disorderly manner and prevent the packer from operating correctly. Consequently, it is absolutely essential that cigarette feeding trays be replaced quickly for the correct operation of high speed packers.

It is an object of this invention to provide an automatic cigarette packer hopper tray feeding device that is inexpensive to build, reliable in operation, has relatively overall dimensions and is capable of accomplishing the replacement of the trays in a sufficiently short time.

The features of the invention and the resulting advantages will be understood from the following detailed description of an embodiment, given as a non-restrictive example, with reference to the attached drawings, in which:

FIG. 1 is a schematic side elevation partially in cross section of an automatic feeding device according to the principles of the invention;

FIG. 2 is a front view along the lines II II of FIG. 1;

FIG. 3 is a view, in perspective, illustrating the over-turning unit of the invention in those instances where the packer hopper is wide enough to be fed with two trays at a time;

FIG. 4 is a view, in perspective, illustrating in greater detail the means for closing the open ends of the trays and the tray container over-turning means;

FIGS. 5 and 6 are views, in perspective, illustrating the container over-turning system and the tray closing and opening mechanism;

FIGS. 7, 8, 9 and 10 show schematically and in sequence, the various operating phases of the over-turning unit;

FIGS. 11, 12 and 13 show schematically and in sequence the operation of the tray extractor;

FIGS. 14, 15, 16 and 17 show schematically and in sequence the various operating phases of the elevator; and

FIG. 18 is enlarged section taken along the lines XVIII XVIII of FIG. 2.

With reference to the drawings and, in general, referring to FIGS. I and 2, the device, according to the invention, comprises a feed conveyor which carries full trays l to a bracket elevator 2 which consists of two endless chains 3 stretched between drive pinions 4 and driven pinions 5. These chains wings define the space in which the cigarette trays are placed. The conveyor is driven by self-braking geared motor 8.

An unloading platform 9 is served by two ejectors 10 which transfer to the platform 9 the empty trays 1 carried by bracket 11. The ejectors 10 are driven by two pneumatic cylinders 12.

The elevator which is used for inserting the full trays into a container 13 of the over-turning device, consists substantially of a bracket 2 whose ends 102 and 202 are provided with grooved rollers 14 slidably coupled to vertical guides 15 and 16. At the center line of bracket 2 is also provided a push roller 17 slidable along vertical guide 18. Finally, each end of bracket 2 is engaged with a branch of endless chains 19, 20, stretched respectively, between drive pinions 21, 22 and driven pinions 23, 24. The upward and downward sliding of bracket 2 along guides 15 and 16 is obtained through the selfbraking and reversing geared motor 25.

FIGS. 14, 15, 16, 17 illustrate in sequence the various operating phases of the elevator. Referring to FIG. 14, bracket 2 on which two trays 1 in side by side relationship have been transferred by the above conveyors, is in the lifting phase. FIG. 15 illustrates the introduction of the trays into containers 13, during which time the cigarettes are subjected to an equalizing action by oblique plate 27. FIG. 16 illustrates the clamping of trays 1 by teeth 28, elastically urged into clamping position by tongue spring 29. FIG. 17 illustrates the descent of bracket 2 which must move to the same level of the conveyor to again receive two full cigarette trays.

FIGS. 11, 12 and 13 illustrate schematically the various operating phases through which the lowering mechanism extracts the empty trays 1 from the over-turning device. This mechanism consists substantially of bracket 11 having ends 111 and 211 (see FIG. 2) which are provided with grooved rollers 30 slidably engaged to vertical guides 31, 32. Each end 111, 211 of bracket 11 is also engaged by a branch of endless chains 33, 34 stretched between drive pinions 35, 36 and driven pinions 37, 38. The upward and downward sliding motion along guides 31 and 32 is obtained through self-braking and reversing geared motor 39. Finally, bracket 11 is provided with tray hooking means, consisting, for instance, of teeth 40 whose number corresponds to that of teeth 28 which engage trays 1 at the bottom to clamp them to containers 13.

FIG. 11 relates to the ascent of bracket 11 which, from the level of the tray unloading platform, indicated with No. 19 in FIG. 2, must come into contact with the trays 1 contained and clamped in containers 13 of the over-turning device. FIG. 12 illustrates the hooking phase, during the ascent of bracket 11, teeth 40 have hooked the trays after having released them from the clamping position operated by teeth 28, as clearly shown in the drawings. FIG. 13 illustrates the extraction of trays 1 from containers 13 and the descent of bracket 11, which must bring the empty trays to the same level as the unloading platform 9 onto which they are pushed, as previously explained, by pneumatically operated 'ejectors 10.

The heart of the feeding device, according to the invention comprises the overturning mechanism which receives the frames or containers 13 having full trays, and, over-tums the trays with a rotation such that the contents, the cigarettes, fall into the packer hopper.

The over-turning unit (see FIGS. 3 to 10 and the assembly drawing of FIG. 1) comprises two pairs of containers 13, 113 and 213, 313, fastened, in an adjustable position, to bars 42, 41 whose ends are carried by carriages 45, 46 and 43, 44 respectively. The carriages are slidable on guides 47 and 48 and are connected by sleeve 49 through which drive shaft 50 is free to revolve. Shaft 50 which is supported by uprights 51 and 52, has earns 53 and 54 keyed at its ends.

Cam 53 cooperates with plates 55 and 56 which are integral with carriages 45 and 44. The forced gripping of the coupling between the cam and the respective plates is obtained by means of helical spring 57 acting in tension which is anchored at its ends with the pair of opposite carriages 44, 45 and keeps the plates in contact with the cam profile. Analogously, cam 54 cooperates with plates 58, 59, the associated spring 57 providing the forced gripping of the coupling. Bracket 60 is fastened to upright 51 to provide two side rectilinear guiding elements 160 and 260 and a circumference arc-shaped middle guiding element 360. Co-operating with these guiding elements is roller 61 rotatably coupled to plate 55 and roller 62 rotatably coupled to plate 56. A bracket similar to bracket 60 is fastened to the other end upright 52 and its guiding elements in a manner similar to the elements 160, 260, 360 cooperate with rollers corresponding to rollers 61 and 62 rotatably coupled to plates 58 and 59.

Containers 13, 113 and 213, 313 are equipped with tray retaining means consisting, for example, of teeth 28 (see, for example, FIG. 4) which engage at the base of said trays, as well as means which close the open top of the trays to allow the containers to be turned upside down without any cigarette being lost and to operate its opening to allow the descent of cigarettes into the hopper after the containers have moved.

The device illustrated in FIGS. 4, 5 and 6 consists substantially of two articulated systems fastened to the outer sides of the containers. Each system comprises a bridge 63, four rocker levers 64, 65, 66 and 67 (see detail in FIG. 6) and two connecting rods 68 and 69. Wings 70 and 71, which close the open top of the trays, are respectively integral with connecting rods 68 and 69 of the two systems. Bridge 63 carries rod 72 on which slidable block 73 is mounted with the interposition of compressed helical spring 74. Rods 75 and 76 are hinged on block 73 and rocker levers 64 and 67.

As a result of the action of spring 74, wings 70 and 74 are held in closed position. By acting simultaneously on the two blocks 73 in such a way as to overcome the action of counter springs 274, rocker levers 64 and 67 are extended to space wings 70 and 71, that is, causing them to assume their opening position. This can be obtained with any suitable means such as pneumatic cylinders 77, preferably one for each articulated system S. The over-turning unit, illustrated as a whole in FIG. 4 is actuated by a geared motor, not illustrated, through which shaft 50 is rotated.

FIGS. 7, 8, 9 and 10 illustrate schematically the various operating phases of the unit. According to FIG. 7, containers 13 and 113 are over-turned in the area of the hopper to discharge the contents of the trays into the hopper while containers 213, 313 are aligned with the elevator which is moving upward to introduce full trays 1 into the containers.

After the tray transfers into the containers, shaft 50 is caused to rotate through an angle of 270. During the first 90 of this rotation (compare FIGS. 7 and 8) carriages 44 and 43 do not move on guides 48 and 47 since respective rollers 62 follow the circular sector of cams 53 and 54, concentric to the axis of rotation of shaft 50. Carriages 46 and 45, however, slide on guides 47, 48 as the respective rollers 61 follow in a pre-established manner, the non-concentric portion of the profile of these cam through the tension of spring 57. By rolling on the rectilinear guides 160 of brackets 60, rollers 61 lift up the respective pawls 78 and move into tangency with the middle guides 360 which are concentric to the axis of rotation. Consequently, the configuration assumed by the assembly at the end of the 90 rotation of shaft 50 is the one shown in FIG. 8.

During the next 180 rotation of shaft 50, cams 53 and 54 rotatably drive the whole assembly as their rectilinear profiles match with plates 55 and 59, while rollers 61 are free to roll on middle guides 360 which, as already noted, are concentric to the axis of rotation.

The purpose of pawls 78 is to prevent carriages 46, 45 from sliding by inertia at the beginning of the assembly rotation on guides 47 and 48 and overcoming the tension of springs 57 which causes rollers 61 to crawl at the inlet of guides 360.

At the end of the 180 rotation, the configuration assumed by the assembly is the one shown in FIG. 9; containers 213, 313 are overturned in the area of the hopper, while containers 13, 113 are aligned with the above lowering device. In these conditions, one end 158 of plate 58 actuates the lower end of a I mircro-switch 79 which is inserted in an electric circuit which controls pneumatic cylinder in such a manner as to open wings 70, 71 so as to allow the cigarettes to descent into the hopper (see FIG. 10). If two pneumatic cylinders 77 are used, two solenoid valves, not illustrated, respectively associated with them are actuated. Altemately, one solenoid valve only could actuate in parallel both cylinders.

While the cigarettes descend into the hopper, the empty trays are extracted from containers 13, 113 by the lowering device (See FIG. 10). After the extraction, shaft 50 is caused to move through a further 90 rotation. The assembly assumes, then, a configuration similar to that shown in FIG. 7, in which containers 13, 113 are in alignment with the elevator which introduces into them the full cigarette trays 1. When photo-electric cell (FIG. 1) detects the complete emptying of the trays contained in containers 213, 313, shaft 50 is caused to rotate 270, thus repeating the cycle.

Keyed to shaft 50 (see FIG. 5) is cyclic cam 81, with a substantially circular profile, having notches 181 and 282 which divide it into two sectors of and 270. Microswitch 82 inserted into the overturning unit drives motor supply circuit which cooperates with this cam.

The beginning of the container overturning cycle, that is, the 270 rotation of shaft 50 is controlled by photo-electric cell 80, provided, however, cigarette trays 1 have been positioned into the containers aligned with the elevator. The end of the 270 rotation, that is, the stopping of the motor is operated by notch 181 of cam 81 through micro-switch 82.

The beginning of the 90 rotation of shaft 50 occurs immediately after the extraction of the empty trays from the containers aligned with the lowering device. A suitable microswitch, not shown, intervenes as soon as the empty trays are extracted from the containers. The end of the 90 rotation, that is, the stopping of the motor which actuates shaft 50, is operated by notch 281 through micro-switch.

It is understood that the invention is not restricted to the embodiment which has been illustrated and described, but many variants and modifications could be made mainly from a constructive viewpoint, and can be applied to fields other than that of the orderly cigarette feed and can in any way be applied to the feed of any type of rod-like articles without departing from the spirit of the invention as defined in the appended claims.

Iclaim:

1. An automatic cigarette packer hopper feeding device comprising a feed conveyor, a tray of cigarettes supported by said feed conveyor, a container to receive a tray of cigarettes, an elevator means for picking up a tray full of cigarettes from said feed conveyor and deliverying said full tray in a substantially rectilinear direct path to an empty container, means for overturning said container with said tray full of cigarettes therein to empty the contents of the tray into the packer hopper, a discharge conveyor, means for extracting the empty tray from the container and transferring it to the discharge conveyor, ejector means for transferring empty trays from the discharge conveyor to a discharge area and means to position said empty container to receive a tray full of cigarettes.

2. The structure of claim 1 wherein the means to overturn said container comprises two bar supports coupled to support two containers and mounted on carriages slidable along parallel guides, each bar support being provided at the ends with a pair of plates, a pair of helical tension springs coupled to urge said bar supports close to each other in opposition to the action of a cam coupled radially to an actuating shaft, said pair of plates being coupled to rollers which follow an alternately pre-established transversing and over-tuming path to discharge the cigarettes into the hopper and present the containers, in turn, to the tray elevator and lowering mechanisms.

3. The structure of claim 2 wherein said cam supports a semi-circular profile and is provided with a relatively large fiat area to guide alternately and cyclically said bar supports between a position of maximum interspacing in which a pair of containers discharges the contents of full trays into the hopper while another pair of containers are aligned with the elevator means to receive from it a pair of trays full of cigarettes; and a position of minimum interspacing in which the containers with the empty trays are moved crosswise away from the hopper and towards the center of the cam and, subsequently, brought, through over-tuming, into alignment with the lowering means which picks up the empty trays from the containers which are again moved outward by the cam rotatiomin alignment with the elevator to receive from it new full trays while the trays of the filled containers discharge into the hopper.

4. The structure of claim 3 wherein a micro-switch is periodically actuated by an end of said pairs of plates when a pair of containers is over-turned in the area of the hopper while another pair of containers is aligned with the lowering means to actuate a pair of pneumatic cylinders which open articulated means for closing the open end of the full trays inserted into the containers.

5. The structure of claim 4 wherein said tray articulated closing means comprises a bridge member hinged to four rocker levers and two connecting rods integral, respectively, with wings which close the open end of the trays, said bridge member carrying a rod on which is slidably mounted a block, a spring interposed between said block and said bridge, rods pivotally coupled to a block and said rocker levers to hold a pair of wing members normally closed, pneumatic cylinders coupled to open said wings when said cylinders are actuated to move said block upward in opposition to the action of said spring to cause the outward extension of said rods which open the tray closing wings.

6. The structure of claim 5 comprising a cam coupled to said drive shaft and having a substantially circular profile and supporting two interspaced peripheral notches which divide said cam into two sectors, respectively, of 90 and 270, and switch means controlled by said cam coupled to a motor to drive said drive shaft.

7. The structure of claim 6 wherein the beginning of the container overturning cycle as determined by the 270 rotation of said drive shaft is controlled by a photo-electric cell circuit when the cigarette trays have been introduced into the containers; and the termination of the cycle is determined by one of said peripherical notches coupled to said switch means.

8. The structure of claim 7 wherein the initiation of the 90 rotation of said drive shaft occurs immediately after the extraction of the empty trays from the containers in alignment with the lowering means, a micro-switch coupled to initiate the rotation of said drive shaft actuated as soon as the empty trays have been extracted from the containers and the termination of the 90 rotation of said drive shaft is determined by the other of said peripherical notch coupled to said switch means.

9. The structure of claim 8 wherein said elevator means comprises a bracket having ends provided with grooved rollers slidable along vertical guides, a push roller in the area of the center line of said bracket slidable along vertical guides, said bracket being engaged with endless chains stretched between drive pinions and driven pinions, the upward and downward sliding of said bracket being operated by a self-braking and reversing geared motor.

10. The structure of claim 9 wherein said elevator means receives full trays from a feed conveyor comprising two endless chains stretched between drive and driven pinions, said chains having links to which are fastened interspaced wings which defines the spaces for accommodating full trays, said feed conveyor being actuated by a self-braking geared motor.

11. The structure of claim 10 wherein said containers are provided with retaining teeth elastically urged by a spring to clamp the trays filled with cigarettes within the containers while said cigarettes undergo a leveling action by oblique plates.

12. The structure of claim 11 wherein said lowering means com rises a bracket, gjrooved rollers coupled to the ends of said racket and slida le along vertical guides, each of said ends being engaged with an endless chain stretched between drive pinions and driven pinions, the upward and downward slidingof said bracket along said guides being operated by a self-braking and reversing geared motor.

13. The structure of claim 12 wherein said bracket supports a first tooth positioned to engage a second tooth which urges said first tooth from a clamping position to hook an empty tray which must be extracted from a container.

14. The structure of claim 13 wherein said lowering means is associated with an ejector which transfers the empty trays, by lateral push, from said bracket to an unloading platform, said ejector being actuated by a pneumatic cylinder. 

1. An automatic cigarette packer hopper feeding device comprising a feed conveyor, a tray of cigarettes supported by said feed conveyor, a container to receive a tray of cigarettes, an elevator means for picking up a tray full of cigarettes from said feed conveyor and deliverying said full tray in a substantially rectilinear direct path to an empty container, means for overturning said container with said tray full of cigarettes therein to empty the contents of the tray into the packer hopper, a discharge conveyor, means for extracting the empty tray from the container and transferring it to the discharge conveyor, ejector means for transferring empty trays from the discharge conveyor to a discharge area and means to position said empty container to receive a tray full of cigarettes.
 2. The structure of claim 1 wherein the means to overturn said container comprises two bar supports coupled to support two containers and mounted on carriages slidable along parallel guides, each bar support being provided at the ends with a pair of plates, a pair of helical tension springs coupled to urge said bar supports close to each other in opposition to the action of a cam coupled radially to an actuating shaft, said pair of plates being coupled to rollers which follow an alternately pre-established transversing and over-turning path to discharge the cigarettes into the hopper and present the containers, in turn, to the tray elevator and lowering mechanisms.
 3. The structure of claim 2 wherein said cam supports a semi-circular profile and is provided with a relatively large flat area to guide alternately and cyclically said bar supports between a position of maximum interspacing in which a pair of containers discharges the contents of full trays into the hopper while another pair of containers are aligned with the elevator means to receive from it a pair of trays full of cigarettes; and a position of minimum interspacing in which the containers with the empty trays are moved crosswise away from the hopper and towards the center of the cam and, subsequently, brought, through over-turning, into alignment with the lowering means which picks up the empty trays from the containers which are again moved outward by the cam rotation, in alignment with the elevator to receive from it new full trays while the trays of the filled containers discharge into the hopper.
 4. The structure of claim 3 wherein a micro-switch is periodically actuated by an end of said pairs of plates when a pair of containers is over-turned in the area of the hopper while another pair of containers is aligned with the lowering means to actuate a pair of pneumatic cylinders which open articulated means for closing the open end of the full trays inserted into the containers.
 5. The structure of claim 4 wherein said tray articulated closing means comprises a bridge member hinged to four rocker levers and two connecting rods integral, respectively, with wings which close the open end of the trays, said bridge member carrying a rod on which is slidably mounted a block, a spring interposed between said block and said bridge, rods pivotally coupled to a block and said rocker levers to hold a pair of wing members normally closed, pneumatic cylinders coupled to open said wings when said cylinders are actuated to move said block upward in opposition to the action of said spring to cause the outward extension of said rods which open the tray closing wings.
 6. The structure of claim 5 comprising a cam coupled to said drive shaft and having a substantially circular profile and supporting two interspaced peripheral notches which divide said cam into two sectors, respectively, of 90* and 270*, and switch means controlled by said cam coupled to a motor to drive said drive shaft.
 7. The structure of claim 6 wherein the beginning of the container overturning cycle as determined by the 270* rotation of said drive shaft is controlled by a photo-electric cell circuit when the cigarette trays have been introduced into the containers; and the termination of the cycle is determined by one of said peripherical notches coupled to said switch means.
 8. The structure of claim 7 wherein the initiation of the 90* rotation of said drive shaft occurs immediately after the extraction of the empty trays from the containers in alignment with the lowering means, a micro-switch coupled to initiate the 90* rotation of said drive shaft actuated as soon as the empty trays have been extracted from the containers and the termination of the 90* rotation of said drive shaft is determined by the other of said peripherical notch coupled to said switch means.
 9. The structure of claim 8 wherein said elevator means comprises a bracket having ends provided with grooved rollers slidable along vertical guides, a push roller in the area of the center line of said bracket slidable along vertical guides, said bracket being engaged with endless chains stretched between drive pinions and driven pinions, the upward and downward sliding of said bracket being operated by a self-braking and reversing geared motor.
 10. The structure of claim 9 wherein said elevator means receives full trays from a feed conveyor comprising two endless chains stretched between drive and driven pinions, said chains having links to which are fastened interspaced wings which defines the spaces for accommodating full trays, said feed conveyor being actuated by a self-braking geared motor.
 11. The structure of claim 10 wherein said containers are provided with retaining teeth elastically urged by a spring to clamp the trays filled with cigarettes within the containers while said cigarettes undergo a leveling action by oblique plates.
 12. The structure of claim 11 wherein said lowering means comprises a bracket, grooved rollers coupled to the ends of said bracket and slidable along vertical guides, each of said ends being engaged with an endless chain stretched between drive pinions and driven pinions, the upward and downward sliding of said bracket along said guides being operated by a self-braking and reversing geared motor.
 13. The structure of claim 12 wherein said bracket supports a first tooth positioned to engage a second tooth which urges said first tooth from a clamping position to hook an empty tray which must be extracted from a container.
 14. The structure of claim 13 wherein said lowering means is associated with an ejector which transfers the empty trays, by lateral push, from said bracket to an unloading platform, said ejector being actuated by a pneumatic cylinder. 